Many people in my Celica club have been asking what fluid to use in their aftermarket clutch type LSDs. The car asks for 75w-90 GL-4 fluid normally (Redline MT-90 is what most people use). Someone was asking if hypoid gear oil would work, but I have no clue if it would or not. Mind you these are FWD transaxles so the fluid has to work well with syncros and the like.